The issue that you described is a common trend with a few particular users on Reddit and YouTube as well. Personally, I do not discriminate. I will work on anything put in front of me and do a good job even if the machine is objectively cheap or bad. If it comes to me for pocket change or for free, I will refurbish it. In fact, I just did a full refurbishment on a Bissell PowerForce and stripped a 2000s Dirt Devil Outlast to restore today. I am aware enough to understand that a lot of people like machines that I do not think are good and there is no reason for me to tell anybody that they cannot like a type of unit. There is also something fulfilling about knowing how to open and fully service all these different machines whether it is a Shark, Dyson, Kenmore, Miele, Oreck, or whatever.
The main vacuum cleaner that I use is my Kenmore 600 Series bagless canister from 2013. It only came with the canister and the hose, so I took a spare NuTone central vacuum power nozzle (one of the old style ones with two rows of bristles and one row of beaters) that I had along with spare Kenmore attachments I found at thrift stores and I use it for everything. I like it because I can unplug the nozzle and suck dirt out of machines I am repairing, use it in my car with the miniature power nozzle, use it around the house regularly, and onward. It has a properly designed multi-cyclonic bin, the filter is washable, and it has a nice and large exhaust filter. It does everything I need it to do.